From 28518f7782310951019d6d28f2a6e9f9fc6e4a1c Mon Sep 17 00:00:00 2001
From: "Darrick J. Wong" <darrick.wong@oracle.com>
Date: Tue, 15 Sep 2020 15:50:35 -0400
Subject: [PATCH] xfs: improve ondisk dquot flags checking

Source kernel commit: a990f7a84edc9941956ea3c1dfb89733c80f9ad0

Create an XFS_DQTYPE_ANY mask for ondisk dquots flags, and use that to
ensure that we never accept any garbage flags when we're loading dquots.
While we're at it, restructure the quota type flag checking to use the
proper masking.

Note that I plan to add y2038 support soon, which will require a new
xfs_dqtype_t flag for extended timestamp support, hence all the work to
make the type masking work correctly.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Eric Sandeen <sandeen@sandeen.net>
---

NOTES: I did not backport the type-vs-flags split, so some of the
naming convenstions are different here.

diff --git a/db/check.c b/db/check.c
index c3dae20..27f6639 100644
--- a/db/check.c
+++ b/db/check.c
@@ -3452,7 +3452,7 @@ process_quota(
 				error++;
 				continue;
 			}
-			if (dqb->dd_diskdq.d_flags != exp_flags) {
+			if (dqb->dd_diskdq.d_flags & ~XFS_DQTYPE_ANY) {
 				if (scicb)
 					dbprintf(_("bad flags %#x for %s dqblk "
 						 "%lld entry %d id %u\n"),
@@ -3461,6 +3461,17 @@ process_quota(
 				error++;
 				continue;
 			}
+			if ((dqb->dd_diskdq.d_flags & XFS_DQ_ALLTYPES)
+								!= exp_flags) {
+				if (scicb)
+					dbprintf(_("wrong type %#x for %s dqblk "
+						 "%lld entry %d id %u\n"),
+						dqb->dd_diskdq.d_flags &
+							XFS_DQ_ALLTYPES, s,
+						(xfs_fileoff_t)qbno, i, dqid);
+				error++;
+				continue;
+			}
 			if (be32_to_cpu(dqb->dd_diskdq.d_id) != dqid) {
 				if (scicb)
 					dbprintf(_("bad id %u for %s dqblk %lld "
diff --git a/libxfs/xfs_dquot_buf.c b/libxfs/xfs_dquot_buf.c
index a3e8ba1..324f528 100644
--- a/libxfs/xfs_dquot_buf.c
+++ b/libxfs/xfs_dquot_buf.c
@@ -39,6 +39,8 @@ xfs_dquot_verify(
 	xfs_disk_dquot_t *ddq,
 	xfs_dqid_t	 id)	  /* used only during quotacheck */
 {
+	__u8			ddq_type;
+
 	/*
 	 * We can encounter an uninitialized dquot buffer for 2 reasons:
 	 * 1. If we crash while deleting the quotainode(s), and those blks got
@@ -59,9 +61,12 @@ xfs_dquot_verify(
 	if (ddq->d_version != XFS_DQUOT_VERSION)
 		return __this_address;
 
-	if (ddq->d_flags != XFS_DQ_USER &&
-	    ddq->d_flags != XFS_DQ_PROJ &&
-	    ddq->d_flags != XFS_DQ_GROUP)
+	if (ddq->d_flags & ~XFS_DQTYPE_ANY)
+		return __this_address;
+	ddq_type = ddq->d_flags & XFS_DQ_ALLTYPES;
+	if (ddq_type != XFS_DQ_USER &&
+	    ddq_type != XFS_DQ_PROJ &&
+	    ddq_type != XFS_DQ_GROUP)
 		return __this_address;
 
 	if (id != -1 && id != be32_to_cpu(ddq->d_id))
diff --git a/libxfs/xfs_quota_defs.h b/libxfs/xfs_quota_defs.h
index afe1ea0..c69dba4 100644
--- a/libxfs/xfs_quota_defs.h
+++ b/libxfs/xfs_quota_defs.h
@@ -31,6 +31,8 @@ typedef uint16_t	xfs_qwarncnt_t;
 
 #define XFS_DQ_ALLTYPES		(XFS_DQ_USER|XFS_DQ_PROJ|XFS_DQ_GROUP)
 
+#define XFS_DQTYPE_ANY		(XFS_DQ_ALLTYPES)
+
 #define XFS_DQ_FLAGS \
 	{ XFS_DQ_USER,		"USER" }, \
 	{ XFS_DQ_PROJ,		"PROJ" }, \